Daily associations between the physical environment and sleep among a diverse, national sample of young adults

We examined daily between- and within-person associations of the physical sleep environment with actigraphic and self-reported sleep.

Young adults in the Future of Families "Young Adult Sleep Study" (n=372; 60% F) self-reported daily for 2 weeks whether 3 sleep environment factors (i.e., temperature, light, and noise) disrupted the previous night's sleep while wearing wrist-actigraphs. Multilevel models examined between- and within-person associations between environmental factors and actigraphic sleep timing, duration, wake after sleep onset, sleep maintenance efficiency, and self-reported sleep quality.

Environmental factors were associated with sleep health in between-person and/or within-person findings. Between-person: A "too hot" environment was associated with greater wake after sleep onset (b = 9.93 minutes, 95% CI [3.64,16.21], P = .006) and lower sleep maintenance efficiency (b = -1.78%, 95% CI [-3.01, -0.54], P = .010). "Too noisy inside" was associated with lower sleep maintenance efficiency (b = -2.97%, 95% CI [-5.24, -0.70], P = .03) and 88% decreased odds of good sleep quality (OR = 0.12, 95% CI [0.02, 0.54], P = .006). A "too bright" environment was associated with 90% decreased odds of good sleep quality (OR = 0.10, 95% CI [0.01, 0.61], P = .010) and later sleep onset (b = 111.05 minutes, 95% CI [26.67, 195.42], P = .010), midpoint (b = 122.95 minutes, 95% CI [41.22, 204.69], P = .010), and offset (b = 131.54 minutes, 95% CI [39.7, 223.40], P = .010). Within-person: A "too hot" environment was associated with lower sleep maintenance efficiency (b = -0.79%, 95% CI [-1.13, -0.45], P<.001) and 45% decreased odds of good sleep quality (OR = 0.55, 95% CI [0.39, 0.79], P = .001) that same night.

Characteristics of the physical sleeping environment (temperature, brightness, and noisiness) were associated with later sleep timing and worse sleep quality but not sleep duration. Future research should examine mechanisms by which environmental factors may affect sleep health.